Patent GB-1009382-A (GB)
Title: Improvements relating to nuclear reactor fuelling arrangements
IPC: G21C19/14
Filed: 1963-02-20
Abstract: 1,009,382. Fuelling reactors. ATOMIC ENERGY OF CANADA Ltd. Feb. 20, 1963 [June 22, 1962], No. 6773/63. Heading G6C. In a fuelling arrangement for a reactor having horizontal channels and employing a pair of substantially similar machines disposed at opposite ends of the channel to be fuelled, the machines being as disclosed in Specification 1,009,381 and each having a ram and a magazine, the machine receiving a spent fuel bundle has a sensing mechanism to detect the axial position of the bundle relatively to its magazine and to complete the final movement of the bundle into the magazine. In Figs. 3, 4 the right-hand end bundle 22a of a train of fuel bundles 22 is shown towards the completion of its movement into the magazine 18 of a fuelling machine 12, the ram 24 of this machine being slowly retracted and the bundles being pushed by the ram 23 of the fuelling machine situated at the other end of the reactor channel 11. The sensing mechanism 21 of the machine 12 is duplicated and only one is described and each mechanism comprises a slidably mounted sensor 30 urged by a spring 32 so that it is biased towards the bundles. In Fig. 3 the sensor is shown engaging an outermost element of the bundle 22a. The outermost elements of the bundles are shorter to provide gaps 26 between adjacent bundles and when a gap becomes opposite the sensor the latter moves into it as in Fig. 6. Rods 35, 35a articulated by a pin 36 connect the sensor 30 with a piston 33 whereby the sensor may be raised from the Fig. 6 position by admitting fluid pressure at 34 or may be locked in the Fig. 6 position by admitting fluid pressure at 29. A ferromagnetic extension 37 of rod 35 co-operates with a coil 38 to provide a signal giving the position of the sensor. During the greater part of movement of the bundles the sensor 30 is held clear by the pressure admitted at 34 but when the gap 26 is about 2 inches from the sensor a " coarse " signal from the ram 24 cuts off the pressure and allows the spring 32 to move the sensor downwards to the Fig. 3 position. A stop mechanism associated with the sensor 30 comprises a sleeve 40 connected by pivot pins 41 to a member 42 terminating in a forked stop 43 straddling the sensor, the sleeve being slidably mounted for movement in a direction parallel to movement of the sensor. The sleeve 40 is driven by pistons 45 acting through rods 49 connected to the pins 41, the pistons being controlled by fluid pressure admitted at 47, 48 and their position being signalled by ferromagnetic extensions 50 co-operating with magnetic switches 51, 52. A deflector 44 also pivoted on the pins 41 has a bearing 53 slidably receiving the rod 35a, this deflector being rotatable on the pins relatively to the member 42, Fig. 10, against the action of return springs (Fig. 9, not shown) by a piston 55 controlled by fluid pressure admitted at 57, 58 and connected to the deflector by a rod 59. A ferromagnetic extension 60 co-operates with a coil 61 to signal the position of the piston 55. After the sensor 30 has been inserted in the gap 26 by the spring 32, Fig. 6, a signal from coil 38 causes fluid pressure to be applied at 29 to hold the sensor locked down and also causes operation of a solenoid valve to move pistons 45 downwardly to insert the forked stop 43 into the gap, Fig. 7. In this position the pins 41 are coaxial with the pin 36 and a stop pin 74 on the member 42 has entered a hole 75 in a stop 76 fixed to the machine 12 to positively locate the stop 43. The stop 43 thus prevents further movement of the bundles 22 by the ram 23. Switch 52 operates a solenoid valve so that the piston 55 is moved down and deflector 44 is pivoted to the Fig. 10 position to pivot the sensor 30 and complete the movement of the bundle 22a into the magazine 18. The control circuit (Fig. 12, not shown) then acts to retract the sensor and stop to their original positions. Specification 1,009,383 also is referred to.